1. E. V. Lyubchenko, G. S. Makeeva, and E. I. Nefedov, Radiotekhnika i roman e back 37 up 25 primelektronika, No. 9, 1665–1682 (1982).
2. A. Jelenski, A. Grub, V. Krozer, and H. L. Hartnagel, IEEE Trans. Microw. Th. Tech.,41, No. 4, 549–557 (1993).
3. R. H. Dean and R. J. Matarese, Proc. IEEE,60, No. 12, 1486–1506 (1972).
4. A. A. Barybin and V. M. Prigorovskii, Élektron. Tekhn., Ser. Élektron. Sverkhvys. Chast., No. 12, 8–14 (1987).
5. S. N. Tolstolutskii, V. S. Mikhailovskii, and Yu. M. Sinel’nikov, Izv. VUZov, Radiofiz.,30, 1498–1504 (1987).